Magnetic pyrometer



Jan. 1, 1929. 1,697,148

'r. SPOONER MAGNETI C PYROMETER Filed Aug. 14, 1926 Fig.1.

l T T 2 2% I8 Fig.2.

uuuuum 24 8 WITNESSES: INJn'NTOR Thomas Spooner.

Patented Jan. 1, 1929.

UNITED STATES PATENT OFFICE.

THOMAS SPOONER, OI EDGEWOOD, PENNSYLVANIA, ASSIGNOR T WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVAN MAGNETIC ryaomnrna.

Application filed August 14, 1926. Serial N0. 129,277.

My invention relates to temperature-indicating and control devices and particularly to magnetic pyrometers.

An object of my invention is to provide a temperature-indicating and. control device that shall be responsive to changes in the mag netic properties of a core associated therewith in response to changes in temperature thereof.

Another object of my invention is to provide a temperature-indicating and control device that shall be effective to produce large indicationsfor small changes in temperature.

In practicing my invention, I provide a magnetic core member and a coils wound thereon in inductive relation to each other. The coils and core member may be considered as a transformer. One of the coils is energized from a source of alternating current. 'I provide also a temperature-indicating and control instrument which is-provided with voltage and current coils so connected to the coils of the transformer that the instrument will indicate the temperature of a body and be adapted to control a circuitinterrupting device in accordance with the temperature of the body. The core member which I employ may be made of a plurality of parts, each of which has a difierent recalescent point.

In the single sheet of drawings, Fig. 1 is a diagrammatic view of the device embodying my invention; and

Fig. 2 is a view illustratlng the devlce shown in Fig. 121s applied to a control c1rcu1t for controlling an electric furnace.

In Fig. 1, a temperature-indicating and control device 11 comprises a transformer 12 and an indicating and control instrument 13. The transformer 12 comprises a core member 14 and a pair of coils 15 and 16 wound thereon. The temperature-indicating and control instrument 13 is provided with a pair of relatively movable coils 17 and 18 (see Fig. 2), a movable indicator and contact member 19, and a scale 20 calibrated in degrees of temperature. The coils 17 and 18 are so connected tothe coils 15 and 16 as to cause a deflection thereof when energized from a source 21 ofalternating current. A switch plurality of energy generated in the coils 16. As the member 22 is employed for controlling the temperature-indicating and control devlce 11. I a

Fig 2 of the drawings illustrates the apphcatlon of my temperature-indicating and control device 11 to the temperature control of an electric furnace 23. The furnace 23 is provided with resistor members 24 which are energized from an electrical-energy source 25. A control device 26 comprises a circuit interrupter 27 and an actuating mechanism 28, the latter comprising a coil member 29, a core member 30 actuated thereby, a pair of links 31 and 32, and a restraining sprlng 33. The coil member 29 is controlled by the instrument 13 and is energized upon the enagement of a contact member 34, insulatedy mounted on the member 19, with a stationar contact member 35.

In the particular application of the device 11, as illustrated in Flg. 2, the transformer 12 is provided with a protecting cover member 36 which encloses the core member 14 and the coils 15 and 16. The core member 14, illustrated in Fig. 2, comprises a plurality of portions 37, 38 and 39. The portions 37, 38 and 39 are of magnetic material but have different recalesce'nt points at which the respective portions become non-magnetic.

The operation of the device illustrated in Figs. 1 and 2 is dependent upon the magnetic properties of the core member 14. Since the coil 15.is energized from a source of alternating current, the coil 16 will have a. voltage induced therein which will be dependent upon the number of turns in the two coils and, the magnetic density in the core 14. As the temperature of the core member 14 increases, the magnetic density thereof will decrease, and the induced voltage of the coil 16 will also decrease.

Since the instrument 13 is provided with a restraining spring 41, the coils 17 and 18 will deflect in accordance with the decrease of the temperature increases, in the core member 14 will decrease until the movable member 19 has caused the contact members 34 and 35 to engage each other to energize the coil 29. Upon energization of the energy consumed.

- the coil 29, the circuit interrupter 27 will be ed to the temperature of a body to be con-.

' coil 14 of the transformer 12.

, ic-pyrometer type in which the operation of effected b thereof.

disengaged from the contact members 42 and trolled comprising a plurality of coils, a plu- 43, thereby deenergizing the resistor memral-part magnetic core member therefor, the hers 24. parts thereof having different recalescence Since the coils of the instrument 13 and points, said coils being inductively coupled the coils of the transformer 12 are in circuit and so connected to said voltage and current with the source 21 of alternating current, coils as to'actuate the movable contact memthe energy generated or consumed by the her in accordance with the energy consumed core member 14, and the voltage generated in in said core member when one of said 0011s is the coil 16 will increase upon a decrease in energized by a source of alternating'cur'rent. the temperature of the core. member 14, be- 7 4. A temperature-indicating and control cause the magnetic properties thereof will device comprising a plural-part core memagain become active at the lower temperature. her, the parts thereof having different re- By employing a plural-part core member 14, calescence points, a plurality of coils mounted as i lu r i Fig. 2, e h f he P s h V- thereon in lnductive relation, one of said coils ing different temperature at which it becomes being energized from a source of alternatmg n'on-magnetic,-'the instrument 13 will have urrent, and an instrument comprising a plua larger range of operation. rality of relatively movable voltage and Car- In the event that the losses in the core memrent oil and a, i of ontact members conber 14.- are not Suflicient to pr du e the trolled thereby, said voltage and current coils sired wattmeter reading, asuitable resistance being so connected to said first named coils m y be in r n rcui W the primary as to cause relative movement of said voltage and current coils.

By my invention, I provide a temperature indicating and Control Of the magnet her a, plurality of coils wound thereon in inductive relation onet'o another, a protective the POI'tlOIl Of the instrument is device around the coils and core 3 the magnetic induction of a member, and a control and indicating instrutransformer in which the core thereofgradt comprising l ti l bl oltag B y i magnetic properties upon inand current coils so connected to said plural creases in temperature. ity of coils as to actuate said instrument when Various modifications may be m e in my one of said plurality of coils is energized from invention without departing from the spirit a source of alternating current in accordance and the scope thereof. I desire, therefore, ith t at t hi h aid or memthat only such limitations shall be placed ber ma b bj t d, thereon as are imposed'by the prior art n 6. A thermal relay for indicating and conthe appended claims. trolling the temperature of a body to be heat- I claim as my invention: ed comprising a transformer having a plural- 1. A temperature-indicating device c0m-, part magnetic core, said parts having difi'erprising a plural-part metallic core member, 'ent recalescence points, said transformer bethe parts thereof having different recalesing subjected to the temperature of the body cence points, apair of coils inductively wound to be controlled, and means having voltage thereon, one of said coils being energized and current coils so connected to the coils of from 8. Source Of al ernating Curren and said transformer as to indicate the temperameans connected in circuit with said coils for t f id b d d t t te id relay. indicating the energy consumed in said core 7, I th l r t tive device, a core member in acwl'dallce with the perature member comprising sections having different magnetic characteristics, a plurality of wind- 2. A temperature-indicating devlce comings thereon, and means connected to Said prising a plural-part metallic core member, windings responsive to temperature changes the parts thereof having different recalesin the core member.

cence points, a plurality of coils wound there- 8; In a th rmal protective device, a core on in inductive relation to each other, one of 'member comprising sections having different said coils being energized from a source of metallurgical compositions, a source of heat alternating current, andan instrument havenergy associated therewith, magnetizing 'ing voltage and current coils connected in means coperating therewith, and means concircuit with said first named coils for inditrolled by said magnetizing means when a eating the temperature to whichsaid core predetermined thermal condition obtains in member may be subjected. the core member.

3. The-combination with an indicatin and 9. In a thermal protective device, a core control instrument comprising relatively member comprising sections having different movable voltage and current coils, and a movmagnetic transformation points, said core able contact member adapted to be actuated member being subjected to a thermal condiby one of said coils toengage a stationary contion to be controlled, windings on said core tact member, of means adapted to be subjectmember having impedances responsive to i Q said transformation points, and circuit conconnected thereto and adapted to be actuated trol means connected to said windings so as by changes permeability. to be controlled thereby. In testimony whereof, I have hereunto sub- 10 10. In a thermal protective -device,'a core scribed my name this 11th day of August, 5 member comprising sections having difierent 1926.

p points of critical magnetic permeability, v

windings thereon, and circuit control means i I THOMAS SPOOIYER. 

